Diagnosing vLLM Buildkite CI Failures

Buildkite logs are public; no login needed.

.buildkite/scripts/ci-fetch-log.sh saves each log as ci-<build>-<job-name>.log, stripped of timestamps and ANSI codes. Existing files are kept; set CIFETCHLOG_FORCE=1 to refetch.

Fetching logs

# All failed jobs in a PR's latest build (current branch's PR if omitted):
.buildkite/scripts/ci-fetch-log.sh --pr <PR>

# All failed jobs in a build (--soft also includes soft-failed jobs;
# --all fetches every finished job):
.buildkite/scripts/ci-fetch-log.sh "https://buildkite.com/vllm/ci/builds/<N>"

# One job — `gh pr checks` URLs (#<job_uuid>) and web UI URLs (?sid=) both
# work; pass "-" as a second argument to stream to stdout:
.buildkite/scripts/ci-fetch-log.sh "https://buildkite.com/vllm/ci/builds/<N>#<job_uuid>"

To clean an already-downloaded log with .buildkite/scripts/ci-clean-log.sh:

./ci-clean-log.sh ci.log

Reference

See [docs/contributing/ci/failures.md](../../../docs/contributing/ci/failures.md) for the full guide: filing CI failure issues, investigating/bisecting, reproducing flaky tests, and daily triage.